At this point I think the investigators know they would have found something by now. But they’re keeping this going for 3 reasons,

1. Find something they weren’t looking for. They have almost unlimited liberty searching all parties involved. They are doing an ordinary political dirt search, but under the official title of a federal investigation. It’s as partisan as it gets.

2. Keep the facade up that “something is fishy” about the Trump administration. This is a helpful talking point right now for literally keeping the democrat(IC!) party alive right now. Their slogan at the moment might as well be, “But have you seen the other guy?”

3. A warning to anyone else who thinks of trying what Trump did. Us normies, the peasants from the heartland of America, who never went to an Ivy League don’t belong in the beltway. When everyone you know in your family has to lawyer up, it is a violating experience, and is meant to send a message that, if you want to play politics where you don’t belong, low-born, nothing is off-limits to us.

Meanwhile, you're lamenting that everybody is picking on Sideshow Don, who's origin story is nothing at all like that. Donny Lawsuit was born with a silver spoon in his mouth and a career path laid out for him, he's not from anywhere near the heartland, and he went to Wharton School of Business ( which is part of the University of Pennsylvania, which is part of the Ivy League).

If people in Washington are mean to him it's because he doesn't belong there, and if there's a lesson for the rest of us it's that self-centered, temperamental man-babies don't belong in the White House. The King of the Birthers is in no position to expect anyone else to respect the office.